健康与遗传心理学研究室知识库

自闭症谱系障碍（Autism Spectrum Disorder，ASD ）是一种神经发育性疾病，核心症状为社交和互动困难，以及限制、重复的行为模式。心理理论缺陷模型认为自闭症人群难以自发的识别、表征他人的心理活动是导致社交困难的原因。然而，只有当我们感知到某个实体具有生命特征，才会自发地启动一系列社会性认 知活动。生命知觉（animacy perception）是指我们能够自发地判断环境中的实体是否具有生命和心理活动的能力。以往研究发现，ASD 群体的生命知觉的确存在非典型表现，比如缺乏对光点小人等生物运动的社会定向，对物体表现出过度的拟人化等。但是以往的研究主要集中在临床群体，缺乏对一般人群中不同自闭 特质个体的生命知觉研究。根据遗传学的研究发现，自闭特质在人群呈现连续分布，其中 ASD 是自闭特质的极端表现形式。高自闭特质个体在日常生活中也表现出与临床群体相似的症状，包括难以维持友谊，无法准确的推测他人的心理活动等等。同时，生命知觉作为底层的社会认知成分，是后续社会定向、社会唤醒以及心理理论等社会互动技能的基础，而以往自闭症的相关模型似乎忽略了该加工过程。因此，本论文提出以下假说，一般人群中高自闭特质个体在生命知觉的两个成分上（感知生命和感知心智）均存在异常，进而导致了非典型的社会认知表现，包括对社会信息的敏感性更低、社会唤醒过高以及心理理论困难。

因此，本论文通过三个研究，对上述假说进行了验证。研究一探究了自闭特质是否会影响个体感知生命的能力，测量了个体对三种生命线索的知觉表现，从自主运动到生物运动，再到面孔生命性线索，蕴含的生命信息逐渐增加。实验一测量了高低自闭特质个体对自主运动生命线索的知觉表现。实验二编制了适用于成年个体的生物运动知觉范式，并在高低自闭特质个体中施测。实验三测量了高低自闭特质个体对面孔生命性（真人脸和假人脸）线索的知觉表现。结果发现，高自闭特质组对自主运动线索的知觉能力与低自闭特质组相似，但是在生物运动 知觉能力和面孔生命知觉能力均与低自闭特质组存在显著差异，分别表现出了对生物运动的注视偏向更弱，以及难以敏锐地感知到面孔的生命性。这些结果说明了高自闭特质个体对与人类刺激相关的生命线索的确存在非典型加工。

研究二以拟人化倾向作为感知心智的测量内容，探究了自闭特质是否会影响个体感知心智的能力。实验四探究了成人群体中自闭特质和拟人化倾向的关系。结果发现高自闭特质个体的拟人化倾向更强，孤独感部分中介了自闭特质和拟人化的关系，但是在控制了孤独感之后，自闭特质仍然会直接影响拟人化倾向。该结果说明，自闭特质的确会影响成人的心智感知能力，自闭特质水平越高，越容易认为非人物体具有心理活动。为了检验上述现象是否源于高自闭特质成年人延续了童年时期的拟人化倾向，实验五对青少年群体的自闭特质和拟人化进行了测 量。结果发现自闭特质和童年时期拟人化倾向呈负相关，并非延续了童年时期的拟人化。综合两个年龄群体的研究结果，我们推测相比于神经典型发育的群体，高自闭特质群体的拟人化倾向的发育轨迹晚于神经典型的个体，在童年时期高自闭特质个体的拟人化倾向发展落后于同龄人，在青少年时期逐渐追上同龄人，但是到了本该拟人化倾向衰退的成年时期，表现出高于同龄人的拟人化倾向。因此，研究二的结果说明，自闭特质的确会影响生命知觉的第二个成分—心智感知。

研究三探究了高自闭特质个体异常的生命知觉对社会定向、社会唤醒和心理理论等高级社会认知的影响，分别从眼动、瞳孔测量学以及行为层面进行测量。实验六测量了高低自闭特质组对不同难度下生物运动的注视偏向，结果没有发现组别差异，高低自闭组对生物运动的注视时间、注视点个数以及访问次数均不存在显著差异，随着实验难度的增加，所有参与者都表现出对生物运动的注视偏向显著降低。但是，当识别生物运动的难度增加时，自闭特质水平越高的个体越倾向于注视倒立的光点运动。该结果说明了高自闭特质个体异常的生命知觉会影响对生物运动的注视定向。实验七围绕瞳孔直径变化指标，探究了高低自闭特质个 体对不同生命度面孔的唤醒度。结果发现，高自闭特质组对真人面孔、模糊生命面孔（即真人与假人混合面孔）的瞳孔直径变化显著大于低自闭组，这可能意味着高自闭特质个体对真人的唤醒度更高并且泛化到了模糊面孔，该实验结果说明了高自闭特质个体异常的生命知觉会影响社会唤醒。实验八探究了高低自闭特质个体对真人和卡通人物的眼神读心能力，结果发现两组参与者的心理理论表现没有显著差异。综合研究三的结果说明，异常的生命知觉的确会影响高级的社会认知。

综上结论，上述研究验证了我们提出的假说，高自闭特质个体在生命知觉的两个成分——生命感知和心智感知——上表现均不典型，对人类对象相关的生命线索感知敏感性更低；对无生命的非人对象表现出过度的心智感知，而且心智感知的整个发展轨迹可能晚于同龄人。更进一步地，高自闭特质个体异常的生命知觉对社会定向和社会唤醒也产生了影响，这可能造成他们对社会信息的低敏感性以及在社交中过度唤醒，进而导致社会交流、互动困难。本论文将生命知觉研究从 ASD 临床群体拓展到了一般人群中的高自闭特质群体，对一般人群中不同自闭特质个体生命知觉能力以及相关的社会认知进行了系统研究，提出了新的解释自闭症社会症状的假说，促进了对不同自闭特质个体非典型社会认知特点的理解。

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with core symptoms of social and interactive difficulties and restricted, repetitive patterns of behaviors. The Theory of Mind Deficit Model suggests that the difficulty of individuals with ASD to spontaneously recognize and represent the mental activity of others is responsible for the social difficulties. However, it is only when we perceive that an entity is characterized by animacy that we spontaneously initiate a range of social cognitive activities. Animacy perception refers to our ability to spontaneously judge whether entities in our environment are alive and psychologically active. Previous studies have found that atypical manifestations of animacy perception do exist in individuals with ASD, such as a lack of social orienting to the point-light displays of biological motion, and showing excessive anthropomorphism of objects. However, previous studies have focused on clinical groups and lacked research on animacy perception in individuals with different autistic traits in the general population. According to genetic studies, it has been found that autistic traits show a continuous distribution in the population, with ASD being an extreme form of autistic traits. Individuals with high autistic traits also show symptoms similar to those of the clinical group in their daily lives, including difficulties in maintaining friendships, inability to accurately surmise the mental activities of others, and so on. Meanwhile, animacy perception, as an underlying social cognitive component, is the basis for subsequent social interaction skills such as social orientation, social arousal, and theory of mind, but previous autism-related models seem to ignore this processing.

Therefore, this thesis proposes the following hypothesis, that individuals with high autistic traits in the general population have abnormalities in both components of animacy perception (perceived life and perceived mind), which in turn lead to atypical social cognitive performance, including lower sensitivity to social information, hyper-social arousal, and difficulties with theory of mind. Therefore, this thesis tested the above hypotheses through three studies. Study 1 explored whether autistic traits affect an individual's ability to perceive life by measuring an individual's perceptual performance of three vital cues, ranging from selfmotivated to biological motion to face vitality cues, which contain progressively more life information. Experiment 1 measured the perceptual performance of individuals with high and low autistic traits to self-motivated cues. Experiment 2 developed a biological motion perception paradigm applicable to adult individuals and administered it to individuals with high and low autistic traits. Experiment 3 measured the perceptual performance of individuals with high and low autistic traits on face vitality (real and dummy faces) cues. Results revealed that the high-autistic trait group perceived autonomous motion cues similarly to the low-autistic trait group, but differed significantly from the low-autistic trait group in both biological motion perceptual ability and face vitality perceptual ability, showing a weaker gaze bias for biological motion and difficulty in acutely perceiving face vitality, respectively. These results suggest that individuals with high autistic traits do have atypical processing of life cues associated with human stimuli.

Study 2 explored whether autistic traits affect an individual's ability to perceive mind using anthropomorphic tendencies as a measure. Experiment 4 explored the relationship between autistic traits and anthropomorphic tendencies in adults. The results found that individuals with high autistic traits had stronger anthropomorphic tendencies, and that loneliness partially mediated the relationship between autistic traits and anthropomorphism, but after controlling for loneliness, autistic traits still directly influenced anthropomorphic tendencies. This result suggests that autistic traits do affect adult mind perception, and that higher levels of autistic traits make it easier to perceive non-human objects as having mental activity. In order to test whether the above phenomenon stems from the fact that adults with high autistic traits perpetuate childhood anthropomorphic tendencies, Experiment 5 measured autistic traits and anthropomorphism in a group of adolescents. It was found that autistic traits and childhood anthropomorphic tendencies were negatively correlated and not a continuation of childhood anthropomorphism. Combining the results of the two age groups, we hypothesize that the developmental trajectory of anthropomorphic tendencies in the high autistic trait group is later than that of neurotypically developing individuals compared to the neurotypically developing group, and that the anthropomorphic tendencies of individuals with high autistic traits lagged behind those of their peers in the development of anthropomorphic tendencies in childhood, gradually catching up with those of their peers in adolescence, but by adulthood, when anthropomorphic tendencies are supposed to be on the decline, showing higher than those of their peers anthropomorphic tendencies. Thus, the results of Study 2 suggest that autistic traits do affect the second component of animacy perception - mind perception.

Study 3 explored the effects of abnormal animacy perception on higher social cognition such as social orientation, social arousal, and theory of mind in individuals with high autistic traits, measured at the eye movement, pupillometry, and behavioral levels, respectively. Experiment 6 measured the gaze bias of the high and low autistic trait groups towards biological motion at different levels of difficulty, and no group differences were found; there were no significant differences between the high and low autistic groups in gaze duration, number of gaze points, or number of visits to the biological motion, and all participants demonstrated a significant decrease in gaze bias towards the biological motion as the difficulty of the experiment increased. However, when the difficulty of identifying biological motion increased, individuals with higher levels of the autistic trait were more inclined to gaze at inverted point-of-light motion. This result suggests that abnormal animacy perception in individuals with high autistic traits affects gaze orientation to biological motion. Experiment 7 explored the arousal of individuals with high and low autistic traits to faces with different degrees of vitality, centered around an index of pupil diameter change. It was found that the change in pupil diameter of the high-autistic trait group was significantly larger than that of the lowautistic group for real faces and fuzzy vital faces (i.e., mixed real and dummy faces), which may mean that high-autistic trait individuals had higher arousal to real faces and generalized to fuzzy faces, and the results of the experiment suggest that the abnormal animacy perceptions of high-autistic trait individuals may affect social arousal. Experiment 8 explored the ability of individuals with high and low autistic traits to read minds in the eyes of real people and cartoon characters, and found no significant differences in the performance of the two groups of participants on theory of mind. Taken together, the results of Study 3 suggest that abnormal animacy perception does affect social cognition.

In summary, the above studies validate our proposed hypothesis that individuals with high autistic traits perform atypically on both components of animacy perception - life perception and mind perception - and are less sensitive to perceive life cues associated with human objects; inanimate non-human objects show excessive mind perception, and the entire developmental trajectory of mental perception may be later than that of peers. Further, the abnormal animacy perception of individuals with high autistic traits also has implications for social orientation and social arousal, which may contribute to their low sensitivity to social information and overarousal in social interaction, which in turn leads to difficulties in social communication and interaction. This thesis extends the study of animacy perception from the ASD clinical group to the high autistic trait group in the general population, and systematically investigates the animacy perception ability and related social cognition of individuals with different autistic traits in the general population, proposes new hypotheses to explain the social symptoms of autism, and contributes to the understanding of the atypical social cognitive characteristics of individuals with different autistic traits.